墨汁鬼伞对重金属铅离子的耐受与富集作用及其在铅离子胁迫下的差异表达蛋白鉴定

铅是已知毒性最大的重金属污染物之一,具有极强的积累性和不可逆性.生物修复环境重金属污染以其成本低、能实现对重金属回收等特点被认为是最有前景的修复技术.墨汁鬼伞被认为具有富集重金属离子的能力,本文首先通过在含Pb~(2+)的固体培养基上培养墨汁鬼伞分析了墨汁鬼伞对不同浓度Pb~(2+)的耐受能力,结果表明当Pb~(2+)浓度低于50 mg·L~(-1)的情况下,墨汁鬼伞的生长不会受到影响;随着Pb~(2+)浓度提高,墨汁鬼伞生长缓慢,菌丝稀疏,菌落形状不规则;当浓度高于500 mg·L~(-1)时,墨汁鬼伞生长明显被影响,并产生色素.进一步分析墨汁鬼伞对不同浓度Pb~(2+)的富集能力表明即使在Pb~(2+)浓度高达800 mg·L~(-1)的情况下,墨汁鬼伞仍然可以富集培养基中的94.7%的Pb~(2+).此外通过分析墨汁鬼伞的差异蛋白,鉴定到一个受Pb~(2+)诱导的14-3-3类蛋白.以上研究表明墨汁鬼伞可以用于环境重金属污染的生物修复.     

Exploration of the key functional proteins from an efficient cellulolytic microbial consortium using dilution-to-extinction approach

In the present study, the cellulose binding proteins(CBPs) secreted by a putative cellulolytic microbial consortium were isolated and purified by affinity digestion. The purified CBPs were subsequently separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis(SDS-PAGE). Using mass spectrometric analyses, eight CBPs were identified and annotated to be similar to known proteins secreted by Clostridium clariflavum DSM 19732 and Paenibacillus sp. W-61. In addition, in combination with dilution-to-extinction approach and zymogram analysis technique, CBPs 6(97 k Da) and 12(52 k Da) were confirmed to be the key functional proteins that influence cellulolytic activities. Moreover, structural domain analyses and enzymatic activity detection indicated that CBPs 6 and 12 contained glycoside hydrolase families(GH) 9 and 48 catalytic modules, which both revealed endoglucandase and xylanase activities. It was suggested that the coexistence of GH9 and GH48 catalytic domains present in these two proteins could synergistically promote the efficient degradation of cellulose.     

缫丝废液的综合利用

缫丝废液中含有丰富的蛋白质，直接排入严重污染环境，废液中的蛋白质能用化学或生物化学方面水解成有用的氨基酸，后者是化学，医药，食品，饲料工业的重要原料，本文报道了缫丝废液中蛋白质酸水解和酶水解的研究结果以及部分酶水解的规律。     

两株海洋细菌新种的分离及BOX-PCR鉴定

对即墨海参养殖池及即墨盐场的底泥样本进行微生物的可培养研究,获得的两株细菌DQHS13与YCSA40,其与亲缘关系最近的模式菌株Marinobacter zhejiangensis及M.segnicrescers的16S rDNA序列相关性分别为98.789％和96.963％,初步判定为海杆菌属(Marinobacte...     

双菌发酵水葫芦压滤液生产单细胞蛋白的研究

水葫芦在我国多个地区泛滥,含水率超过90%,需要就地压滤处理。而由此产生的大量水葫芦压滤液富含纤维素和各种有机物,属于高浓度有机废水,容易造成二次污染,且在目前污水处理技术条件下处理成本较高。通过微生物发酵处理水葫芦压滤液生产单细胞蛋白,可以减少环境污染的同时提高资源的利用率。该试验利用糖化霉菌与酵母混合发酵以提高粗蛋白产量。35℃恒温条件下,当原始COD值为15333.33mg/L时,添加(NH)42SO425.0g/L,先以黑曲霉(Aspergillusniger)发酵40h,然后接种产朊假丝酵母(Candidautilis)酵母发酵32h,菌体回收率可达19.8g/L,COD去除率达到43.65%;当原始COD值为7280mg/L时,添加(NH)42SO46.0g/L,先以黑曲霉(Aspergillusniger)发酵48h,然后接种产朊假丝酵母(Candidautilis)酵母发酵24h,COD的去除率可达81.24%,菌体回收率达1.97g/L,粗蛋白含量达39.76%。     

绿色荧光蛋白标记的大肠杆菌海水中稳定性研究

用绿色荧光蛋白基因( GFP) 标记大肠杆菌K12(K12GFP),检测其在海水中的存活及稳定性.研究结果表明,K12与K12GFP微生物学特性差异不显著,而且两者在高压灭菌海水中的存活曲线也基本一致,说明K12GFP可为进一步研究K12在自然海水中的生态变化提供可靠依据.在高压灭菌海水中,K12GFP存活28 d之久,该菌密度随时间缓慢下降;在过滤海水中,K12GFP存活7 ,该菌密度从107CFU/mL降到102CFU/mL.表明海水的营养成分会对其存活产生较大影响.     

Tomato microtubule-associated protein end-binding protein 1 (EB1) mediates tolerance to salt stress北大核心CSCD

The dynamics of microtubules is regulated mainly by microtubule-associated proteins (MAPs) and plays an important role in plant development and response to environmental signals. End-binding protein 1 (EB1) is a MAP specially binding to the microtubule plus end. Blast search of tomato genome showed two EB1 genes, which were named as SlEB1a (Solyc03g116370) and SlEB1b (Solyc02g092950) in this study. Transgenic tomato plants over-expressing SlEB1a or RNA interfering both SlEB1a and SlEB1b were constructed, and their sensitivity to microtubule depolymerization drug propyzamide and salt stress were analyzed. In this study, we determined the role of tomato EB1 (SlEB1) in the response to salt stress. Compared to the wild-type control plants, OE plants were more sensitive to 1 μmol/L propyzamide, whereas RNAi plants were more tolerant to 1 μmol/L propyzamide; in contrast, OE plants were more tolerant to 100 mmol/L NaCl, whereas RNAi plants were more sensitive to 100 mmol/L NaCl. Thus, SlEB1 might positively regulate salt stress response by negatively regulating the dynamics of tomato cortical microtubules. This study forms a basis for how cortical microtubule dynamics plays a role in plant response to salt stress. © 2018 Science Press. All rights reserved.     

Nutrient depletion is the main limiting factor in the crude oil bioaugmentation process

The biodegradation was considered as the prime mechanism of crude oil degradation. To validate the efficacy and survival of the crude oil-degrading strain in a bioremediation process, the enhanced green fluorescent protein gene (egfp) was introduced into Acinetobacter sp. HC8–3S. In this study, an oil-contaminated sediment microcosm was conducted to investigate the temporal dynamics of the physicochemical characterization and microbial community in response to bacterium amendment. The introduced strains were able to survive, flourish and degrade crude oil quickly in the early stage of the bioremediation. However, the high abundance cannot be maintained due to the ammonium (NH₄⁺-N) and phosphorus (PO₄^3?-P) contents decreased rapidly after 15 days of remediation. The sediment microbial community changed considerably and reached relatively stable after nutrient depletion. Therefore, the addition of crude oil and degrading cells did not show a long-time impact on the original microbial communities, and sufficient nitrogen and phosphorus nutrients ensures the survive and activity of degrader. Our studies expand the understanding of the crude oil degradative processes, which will help to develop more rational bioremediation strategies.     

从制药厂废醪中回收蛋白质

采用凝聚沉降法从制药厂废醪中回收蛋白质。介绍了该法的原理、凝聚剂筛选和工艺条件试验情况。确定了最适宜的工艺条件：废醪等电点的ｐＨ为３．５,它与凝聚剂０．５ｍｉｌ／Ｌ硫酸铁铵溶液的适宜体积比约为（８０～１３０）：１。讨论了温度和时间对凝聚效果的影响。在适宜工艺条件下粗蛋白的回收率可达到９６％以上。     

Novel Foods and Consumer Rights: Concerning Food Policy in a Liberal State

In the public debate concerning novel foods, someconsumer groups claim a consumer right to have accessto certain kinds of food in the market. To discusssuch statements, the paper identifies the reasons thatmay justify liberal states to regulate food. Althoughit defends certain paternalistic activities, itfavours an autonomy-centred food policy. Autonomy andconsumer sovereignty require that certain conditionsare fulfilled. It may be argued that one suchcondition is that the consumer should have choices.Against this position, the paper defends the view thatliberty rights to choose are limited to areas whichare of great importance for personal identity and thegood life. Local decisions in the area of foodconsumption do not have such importance, though globalones may have it. But even if this were true,government activity to protect such liberties shouldbe limited to the guarantee of formal conditions forthe good life of persons. It is not a legitimate taskof the government to safeguard specific conceptions ofthe good life.